Overview

.. 關聯在哪？舉例。 圖例

SPI 為資料傳輸協定，有著以下幾點特色：

• 同步式
• 全雙工
  • 可以半雙工或單工
• 主從式
  • dynamic change of master/ slave
  • 多個 master
• 8 master baud rate prescalers
• slave mode frequency
• SPI TI / motorola mode
• MSB-first or LSB-first
• Hardware CRC
• DMA capability .. BIDI mode / RXONLY (p. 801) .. I2S feature

Device overview

.. image:: /embedded/SPI/STM32F40x block diagram.png STM32F40x block diagram [#]_

.. [#] STM32F405xx, STM32F407xx , STM32F415xx and ... <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/DM00031020.pdf>_ p.

SPI functional description

.. 介紹 pin

.. image:: /embedded/SPI/SPI block diagram.png SPI block diagram [#]_

.. [#] STM32F405xx, STM32F407xx , STM32F415xx and ... <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/DM00031020.pdf>_ p.793

• MISO: Master In / Slave Out data
• MISO: Master Out / Slave In data
• SCK: Serial Clock ( Master -> Slave )
• NSS: (optional) select slave, low-driven

Clock phase and clock polarity

.. Register ======== MSTR: Master selection SSOE: SS output enable SSM: software SS management

|SPI single master/single slave application|

.. |SPI single master/single slave application| image:: /embedded/SPI/SPI 1-1 application.png

STM32F4XX

It has up to 3 SPIs (37.5 Mbits/s), 2 with muxed full-duplex I2S to achieve audio class accuracy via internal audio PLL or external clock

SPI1 can communicate at up to 37.5 Mbits/s, SPI2 and SPI3 can communicate at up to 21 Mbit/s.

Operation

Data transmission

Clock polarity and phase ~~~~~~~~~~~~~~~~~~~~~~~~ Mode numbers ~~~~~~~~~~~~~ .. may know used structure guess: interrupt Independent slave SPI configuration ———————————– Daisy chain SPI configuration —————————— Valid SPI communication ———————– interrupts ———- Example of bit-banging the SPI master protocol ===============================================

Reference

• Serial Peripheral Interface Bus - Wikipedia, the free encyclopedia <http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus>_
• Reference manual: STM32F405xx, STM32F407xx , STM32F415xx and ... <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/DM00031020.pdf>_
• Datasheet: DS8626: ARM Cortex-M4 32b MCU+FPU, 210DMIPS, up to 1MB Flash/192+4KB RAM, USB OTG HS/FS, Ethernet, 17 TIMs, 3 ADCs, 15 comm. interfaces & camera <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/DM00037051.pdf>_

.. need improve

.. _Reference manual: http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/DM00031020.pdf